/**************************************************************
 * bsp_ld06.c
 *
 *  Created on: May 23, 2023
 *      Author: ardakk
 *************************************************************/

#include "lidar_ld06.h"

#include "main.h"
#include "stddef.h"

// CRC8 查表（手册提供）
static const uint8_t CrcTable[256] = {
    0x00, 0x4d, 0x9a, 0xd7, 0x79, 0x34, 0xe3, 0xae, 0xf2, 0xbf, 0x68, 0x25, 0x8b, 0xc6, 0x11, 0x5c,
    0xa9, 0xe4, 0x33, 0x7e, 0xd0, 0x9d, 0x4a, 0x07, 0x5b, 0x16, 0xc1, 0x8c, 0x22, 0x6f, 0xb8, 0xf5,
    0x1f, 0x52, 0x85, 0xc8, 0x66, 0x2b, 0xfc, 0xb1, 0xed, 0xa0, 0x77, 0x3a, 0x94, 0xd9, 0x0e, 0x43,
    0xb6, 0xfb, 0x2c, 0x61, 0xcf, 0x82, 0x55, 0x18, 0x44, 0x09, 0xde, 0x93, 0x3d, 0x70, 0xa7, 0xea,
    0x3e, 0x73, 0xa4, 0xe9, 0x47, 0x0a, 0xdd, 0x90, 0xcc, 0x81, 0x56, 0x1b, 0xb5, 0xf8, 0x2f, 0x62,
    0x97, 0xda, 0x0d, 0x40, 0xee, 0xa3, 0x74, 0x39, 0x65, 0x28, 0xff, 0xb2, 0x1c, 0x51, 0x86, 0xcb,
    0x21, 0x6c, 0xbb, 0xf6, 0x58, 0x15, 0xc2, 0x8f, 0xd3, 0x9e, 0x49, 0x04, 0xaa, 0xe7, 0x30, 0x7d,
    0x88, 0xc5, 0x12, 0x5f, 0xf1, 0xbc, 0x6b, 0x26, 0x7a, 0x37, 0xe0, 0xad, 0x03, 0x4e, 0x99, 0xd4,
    0x7c, 0x31, 0xe6, 0xab, 0x05, 0x48, 0x9f, 0xd2, 0x8e, 0xc3, 0x14, 0x59, 0xf7, 0xba, 0x6d, 0x20,
    0xd5, 0x98, 0x4f, 0x02, 0xac, 0xe1, 0x36, 0x7b, 0x27, 0x6a, 0xbd, 0xf0, 0x5e, 0x13, 0xc4, 0x89,
    0x63, 0x2e, 0xf9, 0xb4, 0x1a, 0x57, 0x80, 0xcd, 0x91, 0xdc, 0x0b, 0x46, 0xe8, 0xa5, 0x72, 0x3f,
    0xca, 0x87, 0x50, 0x1d, 0xb3, 0xfe, 0x29, 0x64, 0x38, 0x75, 0xa2, 0xef, 0x41, 0x0c, 0xdb, 0x96,
    0x42, 0x0f, 0xd8, 0x95, 0x3b, 0x76, 0xa1, 0xec, 0xb0, 0xfd, 0x2a, 0x67, 0xc9, 0x84, 0x53, 0x1e,
    0xeb, 0xa6, 0x71, 0x3c, 0x92, 0xdf, 0x08, 0x45, 0x19, 0x54, 0x83, 0xce, 0x60, 0x2d, 0xfa, 0xb7,
    0x5d, 0x10, 0xc7, 0x8a, 0x24, 0x69, 0xbe, 0xf3, 0xaf, 0xe2, 0x35, 0x78, 0xd6, 0x9b, 0x4c, 0x01,
    0xf4, 0xb9, 0x6e, 0x23, 0x8d, 0xc0, 0x17, 0x5a, 0x06, 0x4b, 0x9c, 0xd1, 0x7f, 0x32, 0xe5, 0xa8};

/**
 * @brief CRC8 计算函数
 * @param package: 数据包数组
 * @param len: 数据长度
 * @return CRC8 校验值
 */
uint8_t CalCRC8(uint8_t package[], uint8_t len) {
    uint8_t crc = 0;
    for (uint16_t i = 0; i < len; i++) {
        crc = CrcTable[(crc ^ package[i]) & 0xff];
    }
    return crc;
}

/**
 * @brief 解析雷达数据帧
 * @param package: 原始数据包（47字节）
 * @param frame: 输出解析后的帧结构
 * @return true: 解析成功且CRC校验通过, false: 失败
 */
bool ParseLidarFrame(LiDARFrameTypeDef* frame, uint8_t package[]) {
    // 1. 检查数据包长度
    if (package == NULL || frame == NULL) {
        return false;
    }

    // 2. 检查帧头
    if (package[0] != HEADER) {
        return false;
    }

    // 3. 检查点数（低5位应为12）
    uint8_t point_count = package[1] & 0x1F;
    if (point_count != POINT_PER_PACK) {
        return false;
    }

    // 4. CRC校验（校验前46字节）
    uint8_t crc_calc = CalCRC8(package, PACKAGE_SIZE - 1);
    if (crc_calc != package[PACKAGE_SIZE - 1]) {
        return false;
    }

    // 5. 解析数据（小端字节序）
    frame->header = package[0];
    frame->ver_len = package[1];
    frame->speed = (package[3] << 8) | package[2];        // 转速
    frame->start_angle = (package[5] << 8) | package[4];  // 0.01度
    frame->end_angle = (package[43] << 8) | package[42];  // 0.01度
    frame->timestamp = (package[45] << 8) | package[44];  // 时间戳
    frame->crc8 = package[46];                            // CRC

    // 【新增】角度插值计算
    float angle_step = (frame->end_angle - frame->start_angle) / 100.0f / (POINT_PER_PACK - 1);
    // 换算成真实角度
    frame->start_angle = frame->start_angle / 100;
    frame->end_angle = frame->end_angle / 100;

    // 6. 解析12个测量点
    int32_t distance = 0;
    uint8_t valid_count = 0;

    frame->distance = 0;
    for (int i = 0; i < POINT_PER_PACK; i++) {
        int base_index = 6 + i * 3;  // 第一个点从索引6开始

        // 【修改】添加角度计算
        frame->point[i].angle = frame->start_angle + angle_step * i;
        frame->point[i].distance = (package[base_index + 1] << 8) | package[base_index];
        frame->point[i].confidence = package[base_index + 2];

        // 【修改】置信度过滤逻辑
        if (frame->point[i].confidence >= 180 && i < 7 && frame[i].distance > 50)  // 取前六个点的数据计算后面数据不准
        {
            distance += frame->point[i].distance;
            valid_count++;
        }
    }

    // 【修改】平均距离计算，只考虑有效点
    if (valid_count > 0) {
        frame->distance = distance / valid_count;
        frame->valid_points = valid_count;
    } else {
        frame->distance = 0;
        frame->valid_points = 0;
    }

    // 计算每圈的最小值
    if (frame->last_angle > frame->start_angle)  // 检测到角度回零（跨圈）
    {
        // 新的一圈开始
        frame->last_round_min_distance = frame->round_min_distance;             // 保存上一圈的最小值
        frame->round++;
        if (frame->distance > 50) {
            frame->round_min_distance = frame->distance;  // 用新圈第一个距离初始化最小值
        }
    } else {
        // 同一圈内，更新最小值,忽略国小的错误值
        if (frame->distance > 50) {
            frame->round_min_distance = frame->round_min_distance < frame->distance ? frame->round_min_distance : frame->distance;
        }
    }

    frame->last_angle = frame->start_angle;  // 更新角度
    frame->count++;                          // 更新次数

    return true;
}